RB1 and small cell lung carcinoma: Fifty-six percent of the tumors had NSCLC-like molecular features, such as lack of RB1+TP53 coalteration and presence of NSCLC-type common mutations including STK11, KRAS, KEAP1, and NFE2L2, while 40% showed SCLC-like molecular features, with RB1+TP53 coalteration, complete absence of mutations in STK11 and KRAS, and exclusive or enriched occurrence of MYCL, SOX2, and FGFR1 amplifications and mutation and/or loss of PTEN [4].